title: Clinical and dermoscopic characteristics of new naevi in adults: results from a cohort study.
abstract: BACKGROUND
  Naevogenesis is a process known to occur throughout life. To date, investigators have made conclusions about new naevi in adults based on results of cross-sectional studies.
  
  
  OBJECTIVE
  To determine the incidence of new naevus development in adults and to describe the dermoscopic morphology of new naevi.
  
  
  METHODS
  A cohort of 182 patients seen at the outpatient dermatology clinic at Memorial Sloan-Kettering Cancer Center between 2000 and 2009 was evaluated with baseline total body photographs. The patients were aged 17 years or older and had presented for routine follow-up surveillance examination at least 3 months after baseline total body photographs. The number of new naevi and the dermoscopic morphology of these naevi were recorded.
  
  
  RESULTS
  Of the 182 patients evaluated, 50 (27%) developed at least one new naevus during follow-up. The incidence of new naevi was 202 per 1000 person-years of follow-up. The most common types of naevi were reticular (47·1%), followed by the homogeneous (22·1%) and complex (reticuloglobular) patterns (15·4%).
  
  
  CONCLUSIONS
  Our results provide support for the theory that there are two distinct pathways of naevogenesis, a dynamic process occurring throughout life. This study demonstrates that the predominant dermoscopic morphology of newly acquired naevi in adults is reticular.
authors.affiliation: Department of Dermatology, Memorial Sloan-Kettering Cancer Center, 160 East 53rd Street, 2nd Floor, New York, NY, 10022, U.S.A.
authors.forename: S A
authors.initials: SA
authors.lastname: Oliveria
authors.forename: S E
authors.initials: SE
authors.lastname: Yagerman
authors.forename: N
authors.initials: N
authors.lastname: Jaimes
authors.forename: A I
authors.initials: AI
authors.lastname: Goodwin
authors.forename: S W
authors.initials: SW
authors.lastname: Dusza
authors.forename: A C
authors.initials: AC
authors.lastname: Halpern
authors.forename: A A
authors.initials: AA
authors.lastname: Marghoob
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D046169:Dermoscopy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008545:Melanoma / Q000473:pathology; D008875:Middle Aged; D009506:Nevus / Q000473:pathology*; D012307:Risk Factors; D017678:Sex Distribution; D012878:Skin Neoplasms / Q000473:pathology*; D055815:Young Adult